Gold washing and saving apparatus



E. C. ROWDON. sow WASHING AND SAVING APPARATUS.

APPLICATWN FILD JU LY27, 1921.

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APPLICATION FILED SULYZY. 1921. 1 3@,592 I Patented Oct. 3, 1922.,

2 SHEETSSHEET 2.

im; ML/NVENTOR Patented Uct. 3, 1922..

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GOLD WASHING AND SAVING- APPARATUS.

Application filed July 27,

To all whom it may concern:

Be it known that I, EDWIN CHARLES Row- DON, a citizen. of the UnitedStates, residing at Sound Beach, in the county of F airfield and Stateof Connecticut, have invented a certain new and useful Improvement inGold ashing and Saving Apparatus, of

which the following is a specification.

. River.

My invention relates to that class of devices which are designed to beused in con nection with dredges, such as are employed for example,along the course of the Snake It is well known that there have beennumerous process machines and dredge apparatuses which have endeavoredto save the fine or flour gold, but they have not been successful. Infact, this is so well recognized that in Bulletin 620 issued by theUnited States Geological Survey, the statement is made (p. 294) Theproblem of saving the line gold is one which has received muchattention. None of themethods so far tried has proved entirely efficientor commercially successful.

My invention has for its object to provide a device which will recoverfrom 10% to 30% more of the fine gold than can be recovered by any ofthe present processes, and to provide means for carrying out my processwhich are so simple as to make it commercially successful.

I have demonstrated in actual test that I recover 66% of the gold whichescapes in the ordinary process. I am aware of the fact that certainattempts have been made to save the line gold by the employment of anelaborate system of sluices. These are exceedingly expensive andpreventthe commercial success of the device. Other devices employ, inconnection with the sluices, special riftles which are designed to savethe coarser particles of gold. In the process employed by me, I entirelyeliminate these expensive parts and accomplish a superior result in thesaving of flour gold.

My means of accomplishing the foregoing objects may be more readilyunderstood by having reference to the acompanying drawing which ishereunto annexed and is a part of this specification, in which Fig. l isa side view partially in section,

1921. Serial NO. 437,931.

showing means for carrying out my improved process.

Fig.2 is a view taken on Fig; l.

Similar reference numerals refer to similar parts throughout the entiredescription.

The drawings are more or less diagram-- matic, being employed for; thepurpose of disclosing operative meansfor carrying out my inventionwithout any reference to the specificdetails of construction whichshould be employed in the installation of a plant embodying my process,and I do not desire to be understood as limiting myself to the structureshown and described, for I believe that the hereinafter containeddisclosure will be ample to enable persons skilled in the art to employthe invention irrespective of the specific structure illustrated in thedrawings.

As shown in the drawings, the material coming from the dredge isdeposited in a hopper 1 and isrsubjected to a stream of water from apipe 2. The material passes through the hopper l on to a grizzly 3 whichis inclined from the horizontal and may be supported in any suitable ordesired manner.

the line 22 in As will be apparent from the drawings, v

the material from the dredge going through the hopper lands on the upperend of the grizzly screen'and the smaller particles and values arewashed down through the screen while the coarser material is rolled offon a chute to the waste pits. The finer materials are carried through "ahopper 5 to a revolving trommel screen 6. This screen is preferably of 1mesh which serves to screen out all material which is larger than thatsize. This material is carried out to an inclined chute 7 which conveysthis material to the waste pit 4. The material which is small enough topass through the mesh of the screen 6 enters with the water into alaunder 8, the bottom of which is inclined so as to convey the materialand water to a second trommel screen 9, the wire of which is preferablyof #8 mesh.

In this screen the material which is too coarse to pass through the meshis discharged on to a chute 10 which carries the coarser material to thewaste pit 4:. Again the fine material and the water pass into a launder11 whence it is conveyed to a third trommel screen 12 which is of #30mesh. This again separates the coarser material which is discharged fromthe screen 12 on to a chute 18 whence the coarser material passes to thewaste pit 4:, while the fine and the water pass into a launder 14whichdelivers both the water and all of the fine material to the amalgamator(not shown).

The screen 12 may be driven by a shaft 15 mounted. in bearings 16 and 17which are carried by suitable supports as 18, the power being applied tothe shaft 15 through the medium of a pulley 19 from any convenientsource of power (not shown). Provision is made for the rotation of thetrommel screen 5) by means of a sprocket 20 carried by the shaft 15 anda chain 21 which extends to a sprocket 22 mounted upon a shaft 23. Thisshaft 23 carries the screen 9 and causes its rotation, the shaft beingmounted in bearings 24 and 25 which are carried by suitable supports 26.

A similar arrangement for the rotation of the screen 6 is employed,comprising a sprocket 27 and chain 28 which extends to a sprocket 29mounted upon the shaft 30 which is carried in bearings 31 and 32, thesebearings being mounted upon supports 33.

It will be apparent from the foregoing description and operation that Ientirely eliminate all sluices or sluices having riflies or pockets inwhich the values are caught and held, to be later removed by lifting theritlles out and cleaning them. I do away with the use of all percussiontables or jiggers of any kind, and further, I do not employ the water towash away the coarser material.

In my process it is my object to save the water and all of the finematerial since I depend entirely upon the screen to get rid of thecoarser material, my reason for this being that the water carries a verylarge amount of flour gold in suspension, and where the water is carriedaway, as in the sluices and other systems, a large percentage if notall, of the flour gold is lost; whereas in my process almost all of thisflour gold is recovered since the water holding it in suspension isdelivered to an amalgamator.

Having described my invention what- I regard as new and desire to secureby Let ters Patent is: i

1. The herein described process for saving flour gold, which comprisesdepositing the gravel upon a grizzly, subjecting the mate rial to water,diverting the coarse material in one direction, carrying the finermaterial and the in another direction to a trommel screen whichseparates the coarser material and diverts it to the waste pit, delivering the finer material and the water to a launder which conveys it to asecond trommel screen where it is again separated, the coarser materialbeing diverted to the waste pit while the water and the finer materialis carried into a second launder, which conveys it to a third trommelscreen which again separates the coarser material which is diverted tothe waste pit, while the fine material and all or the water is deliveredto a launder which conveys it to an amalgamator. 2. The herein describedprocess for saving flour gold, which comprises depositing the gravelupon a grizzly, subjecting the material to water, diverting the coarsematerial inone direction, carrying the finer material and the water inanother direction to a screen which separates the coarser material anddiverts it to the waste pit, delivering the finer material and the waterto a launder which conveys it to a second screen where it is againseparated, the coarser material being diverted to'the waste pit whilethe water and the finer material is carried into a second launder, whichconveysit to a third screen which again separates the coarser ma terialwhich is diverted to the waste pit, while the fine material and all ofthe water is delivered to alaunder which conveys it to an amalgamator.

In testimony whereof, I have signed the foregoing specification.

Enwnv CHARLES ROWDON.

